Lubricating device for electric switches



LUBRICATING DEVICE FOR ELECTRIC SWITCHES Filed Jan. 28, 1939 INVENTOR. ERNST SCHIMANN v A TTORNEY.

Patented Mar. 18, 1941 PATENT OFFICE,

LUBRICATING DEVICE FOR ELECTRIC SWITCHES Ernst Schimann, Bcrlln-Spandau, Germany, as-

signor to Fides Gescllschaft findie Verwaltung und Verwertung von gewcrblichen Schutzrechten m. b. IL, Berlin,

Germany Application January 28, 1939, Serial No. 253,264 In Germany February 16, 1938 3 Claims.

t ct points of electrical switches it has already been proposed to provide oil storage devices which supply 011 to the contact points. This is I performed insuch a manner that the oil storage device is associated with the fixed contacts in that a rotatable roller or the like is provided on the wiper support which is carried round on the rotary movement and thereby slides over the 1 fixed contact.

The invention relates to an oilsupply device for oiling the movable contacts of wipers, preferably of wipers of selectors in telephone installations and consists in providing the wiper with an oil storage device supplying an oil film to the contact points. As an oil storage device a layer of material soaked in oil is used, e. g., a porous material, which is situated in an opening in the spring portion of the contact arm and v conducts the oil owing to capillary effect as well as bythe centrifugal force due to the movement of the arm, so that the contact points are easily supplied with oilso as to form an oil film.

The invention is described with reference to an embodiment which representsa wiper with two contact springs on an enlarged scale, of which the upper spring is removed in order to show the extending piece with the oil storage device in between the two springs.

The separating piece I for the two springs 2 is provided with an opening I which serves to hold the oil storage device of felt or the like which projects like a wick from one front part I. The felt is soaked in oil which passes over the wick l in the neighborhood of the contact points 8 of the wiper and covers these with a thin layer of oilthe eflect being increased by thecentrlfugal force occurring on displacement of the wiper.

Thus a continual automatic supply of oil to the contact points of the wiper is produced. The

. (Cl. 200-166) For the continuous supply of oil to the con renewing of the porous material is easily per-. formed in this construction by lifting up one of the springs 2. For the purpose of more convenient replacement of the oil the storage device can be so arranged that the felt or the like 8 projects sideways out of the spring. Also the oil storage device can be arranged on the contact springs themselves by corresponding arrangement of the wiper.

- What is claimed is: 10

1. A wiper assembly for an electrical switch, comprising twosimilarly shaped wiper blades each having a shank portion and, at or near its outer extremity, a contact portion, means including a substantially flat spacing member be- 18 tween the shank portions of said two blades for clamping said blades in a superimposed but spaced apart relationship, said spacing member having a slot opening toward the contact portions of said bladu, and a pad of oil soaked ma- 2 terlal in said slot and in contact with the inner surfaces of both of said blades.

2. Arotarywiperassemblyasclaimedin claim 1, wherein said slot is so configured that its walls converge toward the contact portions of said 25 blades, and wherein said pad is substantially wedge shaped to dovetail with the convergent walls of said slot thereby to prevent movement of the pad in the slot toward the contactportions of the blades. so

3. An electrical contact, including a substantially flat member having a'slot opening upon and extending inwardly from one edge, two metallic members each'having a flat portion and a contiguous contact portion, and means for as fastening said last two members to the opposite sides of said first member with their flat portions covering the sides of said slot to form a well and with their contact portions extending slightly beyond the opening of said well.

ERNST SCHIMANN. 

